Desert planet
A desert planet, also known as a dry planet, an arid planet, or a dune planet, is a type of terrestrial planet that is arid at the surface level.
Deserts can be cold or hot, and even retain water, like Antarctica or the Sahara on Earth; however, desert planets are arid across their entire surface. Mars is a prominent example of a desert planet with a tenuous atmosphere.
But also other arid planets with atmospheres more as well as less dense have been identified as desert planets, like Venus and Mercury.
History
A 2011 study suggested that not only are life-sustaining desert planets possible, but that they might be more common than Earth-like planets. The study found that, when modeled, desert planets had a much larger habitable zone than ocean planets. The same study also speculated that Venus may have once been a habitable desert planet as recently as 1 billion years ago. It is also predicted that Earth will become a desert planet within a billion years due to the Sun's increasing luminosity.A study conducted in 2013 concluded that hot desert planets without runaway greenhouse effect can exist in 0.5 AU around Sun-like stars. In that study, it was concluded that a minimum humidity of 1% is needed to wash off carbon dioxide from the atmosphere, but too much water can act as a greenhouse gas itself. Higher atmospheric pressures increase the range in which the water can remain liquid.